'Right now, I've got a big knot in my stomach," says Sturla Gunnarsson, looking just a little ashen around the mouth. "The film just came back from the lab. It's so fresh, it's still wet."

Gunnarsson, the Canadian veteran director of Scorn and the award-winning Such a Long Journey, is talking about his latest work -- and his biggest to date -- Beowulf and Grendel. A lavish and somewhat explosive period piece set against the bloody backdrop of the barbarian invasions across Europe, Beowulf and Grendel, which won't open in theatres until March, is what Gunnarsson calls a loose adaptation of the 9th-century Anglo-Saxon poem.

Embellishing the text with new dialogue and new characters, Gunnarsson and screenwriter Andrew Rai Berzins attempt to sculpt a poetic film from this monstrous work. Fleshing out themes of religious conversion, romance and personal crisis in the heart of the warrior, both the writer and director were going deep in an attempt to capture the tragically timeless spirit of war.

"It's just a little stressful right now because you want to know how an audience is going to react to what you've done," says Gunnarsson. "Every step along the way you are making decisions, hoping that you've made the right ones -- but you don't know until you've screened it for the first time in front of an audience."

Gunnarsson survived that first evening at the Toronto International Film Festival. So did the audience. The film also screened at the Vancouver International Film Festival.

Shot entirely in Iceland, Gunnarsson's ancestral home, the movie is basically a bare-bones examination of life and death.

"I saw every day as a day of discovery," Gunnarsson says. "What struck me over the course of making this film in Iceland, where the cameras were literally blown over by the wind, was just how elemental the story is.

"We might read on the page that there is a hand-to-hand battle raging on, but when you see that battle played out against the backdrop of this huge, rugged landscape, it takes on a whole new meaning," he says.

"Weather became this unwritten character. There was one day where the assistant director was literally blown off her feet by the wind, and even though all that happens off-camera, it's affecting everyone because you can't help but feel very small when a volcano is going off in the background."

Sarah Polley says the shoot was a physical and logistical challenge that pushed everyone to the limit, but there's nothing that makes you feel so alive as a close encounter with the raw force of mother nature.

"The whole thing was like an Outward Bound experience. You really learned about the mechanics of survival, from being outside, to getting in a vehicle trying to navigate narrow roads on cliffsides. So much of the experience was just plain terrifying," she says.

Polley used her adrenaline-fuelled energy and insight to craft her character Selma, a witch who fleshes out certain human elements in the key human character of Beowulf, the great warrior, played by Gerard Butler.

"Sturla had such a new and interesting take on the material," Polley says. "And for me, part of the attraction to Selma was how aggressive she was. I've never played anyone quite like her before."

Polley's career started in childhood with such projects as Road to Avonlea and she's generally played more introverted, contained women -- from the young survivor in The Sweet Hereafter to the quiet party girl in Doug Liman's Go to a cunning portrayal of a young, inexperienced artist in Guinevere.

"Selma also has a lot of sexual power, and she's not afraid to use it -- which is something else I was drawn to because sexuality isn't something I've really had a chance to explore on screen."

Polley says there's a difference between being a sexual object and being a sexual force. She's been the passive object of desire before, many times, but taking control and being in charge of the moment was entirely empowering for the international star.

"As human beings, I think we have to reinvent ourselves and the way we work every time, otherwise you do get stale. I like to work with different directors because it changes my approach. I've been working since I was eight years old and some directors create a whole, safe environment for you -- like Atom Egoyan or Isabel Coixet -- and some throw you into a situation where you react," she says.

"I think there's a lot to be said for both techniques. And you know, I don't even mind working with total assholes because you never know what's going to be potentially useful to your performance. Beyond that, there's also just my desire to understand how directors work."

Polley has directed a few short films and has plans to direct again, but for now, she's busy with new projects for Coixet and German director Wim Wenders, who directed the Sam Shepard script Don't Come Knocking.

"I see everything as a learning experience," she says. "Beowulf and Grendel will definitely go down as a bigger lesson -- in survival, as much as acting."

Gunnarsson, a tall, Nordic, rugged man who gives off waves of calmness despite his case of opening-night jitters, said he drew nothing but creative energy from the harsh landscape.

"I felt so profoundly alive, I began to understand the whole pagan tradition because every element has its own language, it's own mystery, it's own power. How could they not seem godlike?" he says.

"This story survived the ages ... It was lost for more than 500 years, then found, half burnt in the middle of a barn. It remains because it's the cornerstone of the hero myth, and takes it back to the pagan roots -- where heroes were allowed to be flawed. It's only once you get into the monotheistic universe that heroes are suddenly expected to be perfect.

"I wanted to explore this era of tribalism because it's upon us once again -- this idea of people being bound by blood or religion and working to kill the other. It's an eternal story about the nature of the human condition ... and this was my way of talking about modern problems: To go back to where it all began and look at the oldest known work of English literature with a modern sensibility."